Pulp-screen.



P. P. WESTBY.

PULP SCREEN.

Awucnlou man :uns 9.19m.

1,225,198. Patented May 8,1917.

3 SREETS-SIIEET l.

P. F. WESTBY.

PULP SCREEN.

APPLICATION man :un: 9. |913.

1,225,198. Patented Muy s, 1917.

3 SHEETS-SHEET 2.

IHI I1 www 3mm w wm P. P. WESTBY.

PULP SCREEN.

APPUCAHON fluo luna 9. 1913.

Patented Muy 8, 1917.

1,225,198- 3 www 3.

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FEDER P. WESTBY, OF PETERBOBOUGH, ONTARIO, CANADA.

PULP-SCREEN.

Specification of Letters Patent.

Application filed June 9, 1913. Serial No. 772,568.

To all whom it may concern Be it known that I, lrniin P. lVns'rnY,subject ot the King of Norway, residing at Peterborough, in the countyof Peterborough, Province of Ontario, Canada, have invented certain newand useful Improvements in Pulp-Screens, of which the following is aspecification.

My invention relates to paper making machinery and particularly to apulp screen of the horizontal type, adapted to separate the tine librousor usable portion of the pulp from the coarse or unusable portionthereof.

The pulp screen forming the subject inatter hereof is of that typeemploying au annular perforated screen, within which is mounted arevoluble distributer` operating to discharge the pulp by centrifugaltendency against and through the screen.

The object of the invention is to simplify the structure as well as themeans and mode of operation ot' such machines, whereby they will notonly be cheapened in construction, but will be more ellicient in use,economical in operation, easily operated, readily ae. cessible andunlikely to get out of repair.

A further object of the invention .is to provide improved pulp feedingmeans whereby the rotary distributor will be supplied with the pulpequally throughout itsl circle of operation, whereby the entire screensurface may be utilized, thereby increasing the eiliciency and capacityof the machine.

Vith the above primary and other iuci dental objects in view as willmore fully appear in the specification, the invenlion consists of thefeatures of construction, the parts and combinations thereof and themode of operation or their equivalents as herein after described and set'Forth in lhe claims.

Referring to the drawings, Figure l is a longitudinal, vertical,.sectional view of the assembled machine. Fig. is a transverse,vertical, sectional viewon line .fr of Fig. l. 2l is a side elevation ofthe runner or distributer removed. from the machine. Fig. l is a detailperspective view of the screen supporting frame.

Lilie parte are indicated by similar characters of reference throughoutthe several views. j

In constructing the machine there is employed a main frame or housing,comprising oppositely disposed heads l and il, connected at their upperportion by an interposed water supply chamber or conduit 3 and at thelower portion by a base member 4, in which is formed a receiving chamber5 for the screened pulp. This frame is provided with removable arcuateside members 6. These side members C may be secured in any desiredmanner, but in the drawings have been shown with dowels or studs 7adapted to engage sockets 8 upon the base member l, and clamping memberslocated about the peripheries ot' the heads l and Q. These arcuate sidemembers (i in conjunction with the base member i form a substantiallycylindrical housing or casing.

Removably supported in a concentric position within the casing orhousing is an annular screen plate 1l). This screen plate is preferablydivided into a plurality of arcuate sections, each supported upon aframe member comprising longitudinally disposed angle bars l1, connectedby arcuate ribs 12. ln order that the screen surface may be as littleobstructed as possible, the. arcuate ribs l2 of the supporting frame,are spaced away troni the screen plate 10 as shownin Figs. 2 and l. Theend` of the screen plate l() is secured lo the longitudinal angle bars1l, while the medial portions of the plate are supported on bosses orlugs 13. projecting inward from the arcuate ribs 12.

ln order to obviate the liability of breakage oi' the screen platedue tothe great pressure and strain to which it is subjected, the centralportions of the plate are rendered resilient or slightly yielding byforming the bosses or lugs 13 of rubber or other resilient material. ltis to be understood that the resiliency ot the screen plate is notessential. but under certain conditions is desirable. Helical springsmay be substituted for the rubber supports. ln lieu of the resilientbosses 13, such bosses or supports may be formed integral with thearcuate ribs 12. ln the event that the bosses are formed of a resilientmatter. a second resilient collar or washer li is preferably located onthe inner side of the plate and the screen plate and collars are.secured to the arcuate ribs l2 by means of a conical headed bolt 15. Inthe event that solid, integral bosses 13 are employed, the secondresilient collar Patented May 8, 191'?.v

CAT

may be omitted and an ordinary metallic washer employed instead.

The conical head of the bolt 15 affords no place for the lodgment of thefibrous particles of pulp and serves to direct such portions of the pulpas may strike the bolt head onto the screen plate. The sectional screensand frames thus formed may be bolted one to the other, but arepreferably secured by means of clamps 16 which engage the radial flangesof the angle bar 11. The screen plates and frames are supported uponannular flanges 17 upon the inner face of the heads 1 and 2. The lowerportion of the heads 1 and 2 are provided with a second inwardprojecting [lange 18 parallel With the flange 1T to form an intermediategroove within which the lower portion of the screen plate and framesengage. The sectional screen plate may be readily removed for inspectionor replacement by the removal of the arcuate side members 6.

Journaled in suitable bearings 19 upon the heads 1 and 2, is alongitudinal shaft J0 carrying at one end a drive pulley 21. 'lhe shaftis located concentric with the screen plate and casing. Projectinginward from the head 2 and concentric with the shaft 20, is a` pulpfeeding chamber 22. This chamber comprises a circular stepped housing,the successive steps being concentric one with the other, and ofsufficient difference in relative diameters to permit pulp feeding portsor orifices 23 in the transverse face of each successive step. Byreference to Fig. Q, it will be seen that these ports or orifices Q3 areof different relative sizes according to their height. It will be notedthat the ports or orifices adjacent to the top of the feeding chamberare much larger than those at the bottom thereof. The pulp dischargedwithin the screen plate will tend to settle or concentrate in the lowerportion thereof. by the influence of gravity. This is to some extentcompensated for, by the variation in the relative sizes in the ports,whereby a larger portion of the pulp Will he discharged into the upperportion of the runner or distributer. The variation of the relativesizes of the port further compensates for the difference in pressure orhead.y under which the pulp is discharged to the higher and lowerorifices.

rThere is formed in the head 2 an annular chamber or recess Q4,communicating throughout its entire extent with the feeding chamber Thisannular chamber or recess is provided with a pulp inlet 25. The pulpentering through the inlet tills the annular recess 24 passing thenceinto the feeding chamber 22, from which it is discharged in alongitudinal or axial direction through the ports or orifices Q3.

Secured upon the shaft 2O adjacent to the feeding chamber 2Q, is a hub26, by which are carried a plurality of radially disposed wings or Yanes27, forming the runner or distributor. These wings or vanes projectradially to points adjacent to the annular screen plate and extendlongitudinally throughout the width of the screen plate. The wings I(oYerh-ang the feeding chamber and are notclual or recessed to correspondwith the successive steps thereof. It is to be noted that each shoulderor ol'l'sct of the wings 2T. extends inward beyond the orifices or ports112i of the corresjmndine' step ofthe feeding chamber inasmuch as theterminal port or orifices of the feeding chamber 2; are located closelyadjacent to the shaft 2t) and the internualiate sparc between successivewings or Yanes is contracted in such close proximity to the hub QPLalternate wings an` recessed or cut a way adjacent to the last tace orstep of the feed ing chamber. as shown at :Inl M' their outer end theuings or Yanes 2T are connected one with the other by the annular rim2th surrounding the feeding chamber "22. The wings` are I'nl'thcrsupported and connected one with the other. by a trans- Yorsc web ill,extendingl adjacent to the periphery ot| the runner or distributcr. andsubstantially diriding the chamber of the machine into two compartmentscommunirating one with the other through an annu lar opening about theperiphery of the web, adjacent to the screen plate. Beyond the web il()or in the second compartment the wings or Yanes 27 are pif-ejectedlongitudinally as at 3l. to overhang an inward annular projectioncarried by the head 1 and provided with a peripheral flange forming anannular channel An outlet 35 for the tailings and coarse or unusableportions of the pulp` leads from this channel through the head l.

water supply conduit 36 leads to the water chamber El which is providedwith a plurality ot jaifoi'atioiis adapted to disA charge water in aspray upon the screen plaie l0. branch conduit 3T discharges a stream ofwater into the annular channel Ell to wash the tailings which arecollected therein througli the outlet 35.

rlhe Yanes ai", in addition to being radially disposed about the huh t),are inclined somewhat to the axis of rotation as clearly shown in Fig.3. The portion of the Yanes 27 overhanging the feed chamber 2Q. isinelined in a forward direction while the extremity 3l is locatedslightly to the rearwardn in relation to 'the direction of rotation.This causes the pulp discharged. from the feed chamber QQ. and which iscarried outward or radially by centrifugal tendencies to graduallytravel throughout the length of the vanes or wings. The finer and usableportions of the pulp will be dis charged radially by centrifugaltendencies against and through the perforated screen plate l0, into theannular chamber intermediate the screen plate and the cover scction o,through which chamber the screened pulp Will pass to the receivingchamber 5, located in the base of the machine. From this chamber 5 theusable, pulp is discharged through an outlet 38. The heavierl andcoarser portions of' thc pulp will gradually travel longitudinally uponthe blade or wing, due to the inclination of such wings to the axisl orrotation, while at the same time they will be moved outward under centritugral tendencies. The unusable portions of the pulp will finally passthe periphery ot' the We) 3() and will be discharged from theovcrhanging portion 31 of the vane into the annular channel 34, fromwhich they will be flushed by Water from the branch conduit 3T andfinally discharged from the machine through the outlet Located upon therear side of each of the wings or vanas 2i'. adjacent to the cdjrethereoic and parallel with the perforated screen plate l0, is alongitudinal flange or ledge 39, formingi a recess lll innnediatelybeneath such ledge. As the runner or distributor rotates at a very highrate of speed, the tendency will be to forni a partial vacuum within therecess Ul immediately barl: of cach Wing'. This partial vacuum willcreate a suction upon the screen plate 10, tending to free it from thecoarser particles ivhich find lodgment thereon, drawing' such particlesaway from the screen and again into the influence ot the blades or vanes2T, upon which such particles will move longitudinally a limiteddistance before being again projected upon a screen. 'Thus such coarseparticles are repeatedly projected from and returned to the influenceof' the wings or vanes until every particle ot line or usable materialis separated therefrom by which time the coarse particles have traveledbeyond the transverse web I3() and are deposited by the extension 3l inthe waste or tailing channel 34.

lt to be noted that the outer edges oi the ports 23 are flush with thewalls of the feeding chamber 22. Thus there will he no obstruction tothe free discharge of the pulp from the chamber and no tendency l'or theheavy portions of the pulp to settle n'ithin the feeding;V chamber 22and remain therein. The otlsets or shouldered portions ot' the ninos orvanes by extending entirely across the ports 23 and closely adjacentthereto, create a suction upon the feeding chamber, which serves to drawthe pulp through the ports and into the distributer. This action of thedistributer assists in preventing the pulp settling within the feedingchamber and accelerates the fionT of pulp therethrough.

From the above description it will be apparent that there is thusprovided a device ot the character (inscribed, possessing the particularfeatures of advantage before em1- merated as desirable, but whichobviously is susceptible of modification in its form, proportion, detailconstruction or arrangement of parts, without departing :from theprinciple involved or sacrificing any of its advantages.

lVhile in order to comply with the statute, the invention has beendescribed in language more or less specific as to certain structuralfeatures, it is to be understood that the invention is not limited toany specific details, but that the means and construction hcreindescribed comprise but one inode of putting the invention into effect,and the invent-ion is therefore claimed broadly in any of its possibleforms or modifications uithin the scope of the appended claims.

llaving thus described my invention, I claim,

l. ln a pulp screening' machine, a casing', a screen member, a steppedfeeding chamber projectinev within the casing, said member havingdisehalga'e ports iu the transverse fares of' succeedingv steps, and arotary distributer within the casing. the blades ot which have steppednotches therein conforming;` to the contour ot' the feeding' chamberwhich they overhang.

ln a pulp screeningv machine. a casing. a screen member. a rotarydistributer therein` a `feeding chamber projecting within the casinar ina position concentric with the distribnter and ha ving pulp dischargeports located in different vertical planes substantially ]n rpendicularto the axis of rotation of the distributer.

ln a pulp screening machine. a casing, a. screen member, a rotarydistribnter. a fccdiney chamber projecting into the distributer in aposition concentric therewith, said feeding; chamber having pulpdischarge orifices located, at dillicrent distances from the axis otrotation ol the distributer and in ditlerent planes substantiallyperpendicular thereto.

l. ln a pulp screening machine, a casing, a screen member, a rotarydistrilnlter, a stepped feeding chamber projecting within the casina'.said feeding chamber having pulp discharge ports in the transverse facesoi succeedingr steps.

ln a pulp srivccninnl machine, a casing'. a screen member. a circularVfeeding chamber projecting within the easinggr concentric with thedistrilgnlter and having concentric pulp discharge ports in thetransverse tace thereof and coincident with the peripheral Wall of thechamber, and a rotary distributer.

(i. A pulp screening n'iachine. a` casing, a screen member. a recessedrotary distributor therein rotatingr on a horizontal axis, a concentricecding chamber extending Within the recess of the distributer, and aseries of ports in said feed chamber discharging in an axial directionand located in different planes throughout the axial length of thedistributer.

T. In a pulp screening machine, a casing, a screen member, a rotarydistributor therein rotating on a horizontal axis, a feeding chamberprojecting within the casing having a plnralitv of arcuate pulpdischarge ports therein. said ports varying in length accordingto theirrelative locations, the uppermost ports being larger than the lowermostports.

S. ln a pulp screening machine` a casing, a screen member. a rotarydistributor therein. a stepped feeding chamber, a plurality ol` pulpinlet ports in the llat faces of each step, said ports of tach stepbeing of differoui areas in inverse proportion to the head or pressureunder which the pulp is discharged through the individual ports.

9. ln a pulp screening machine, a casing, a .screen member, a steppedfeeding chamber projecting within the easing. haring pulp dischargeport.- located in ',lillerent planes in the transrerse fares thereof,and a rotary distributer recessed lo conform to the contour of thefeeding chamber.

l0. In a pulp screening machine, a casing, :i stepped feed chamberprojecting within the easing having pulp discharge ports located indilferent planes in the transverse faces thereof. and a rotarydistrilmter, having a plurality of substantially radially disposedblades, each of the blades being adapted to extend inn'ard toward theaxis of the distrihuter beyond the pulp discharge ports.

1l. lu a pulp screening machine, a casing, a screen member, pulp feedingmeans, a rotary distributer rotating on a horizontal axis comprising aplurality of substantially radially disposed blades, a transverse webconnecting said blades and extending beyond the radial position of thepulp feeding means. said web dividing the casing into tn'o compartmentscommunidating one with the other about the peripheli'y of the Web, andan outlet conduit for tailings leading from one of the compartments.

l?. In ar pulp screening machine, a casing, a screen member, pulpfeeding means, a rotary distributor comprising a pluralityv ofsubstantiallyv radially disposed blades inclined to the axis ofrotation, a transverse web connecting said blades beyond the peripheryof which said blades extend, said blades being correspondingly inclinedat opposite sides of said web whereby heavy particles of pulp will heinduced to travel toward said Web beyond which they are deposited by theaction of said blades.

13. In a pulp screening machine, a casing member, pulp feeding means, arotary distributer within the casing and an inward extension on one endof the casing having an external peripheral channel therein adapted toreceive the tailings.

14. In a pulp screening machine, a casing, a screen member, pulp feedingmeans, an inward extension projecting from one end of the casing andconcentric therewith and having a peripheral channel therein, and arotary distributer having a plurality of substantially radially disposedblades overhanging the annular channel.

15. In a pulp screening machine, a casing, a screen member, pulp feedingmeans, a rotary distributor having a plurality ot' substantiallyradially disposed blades, each blade having on its rear Side in relationwith the direction of the rotation. a longitudinally disposed riblocated adjacent to the edge of the blade.

16. In a pulp screening machine, a easing, a. screen member, pulpfeeding means, a rotary distributer having a plurality of substantiallyradially disposed blades and means to induce a suction upon` the .screen.member in the rear ol each bla dc to clear the screen member ofadhering particles.

17. In a pulp screening machine, a casing, a screen member, a pulpfeeding means, and a rotary distribute-r comprising a plurality oftangentially arranged blades, each blade being inclined to the axis ofrotation.

18. In a pulp screening machine, a horizontally disposed cylindricalcasing, a cylindrical screen member concentrially located within thecasing, a horizontal shaft in axial alinement with the casing and screenmember, a stepped circular horizontally disposed feeding chamberextending Within the casing concentric with the shaft, said feedingchamber having pulp discharge orifices in the, vertical faces of eachsucceeding step, and a rotary distributer carried on the shaft adjacentto the feeding chamber.

19. In a pulp screening machine. a horizontally disposed cylindricaleasing.` a cylindrical screen member concentrically located within thecasing, a horizontal sha tt in axial alinement with the casing andscreen member, a stepped circular horizontally disposed feeding chamberextending Within the casing concentric with the shaft, said feedingchamber having pulp discharge orifices in the vertical faces of eachsucceeding step, the area of those discharge orifices beneath the levelof the shaft being less than that of those above the level of the shaft,and a rotary distributer carried by the shaft.

20. In a. pulp screening machine, a horizontally disposed cylindricalcasing, a cylindrical screen member concentrically located within thecasing, a horizontal shaft in axial alinement With the casing and screenmember, pulp feeding means leading to the casing, a rotary distributercarried on the shaft, a concentric annular extension projecting inwardfrom one end of the cylindrical cas- .l (Mi lili ing ,and having aperipheral {iange forming a vertically disposed annular' channel aboutsaid extension to receive the tailings.

21. In a pulp screening machine, a horizontally disposed casing, acylindrical screen member eoncentrically located within the easing, ahorizontal. shaft in axial alinement with the casing and screen member,pulp feeding means leading to the casing, a rotary distributer carriedby the shaft, comprising a plurality ot' substantially radially disposedblades, each blade being projected raarward adjacent to its Aedge toform a recessed rear face.

Q2. In a pulp screening machine, a easing, a cylindrical screen membertherein, a supporting frame for the screen member, including annularribs of diilerenl` radius than that of the screen member, bosses locatedat several points upon the ribs with which the` screen member is engagedand by which the screen member will be spaced zlvvay from the supportingribs, and a rotary distributer.

In a pulp screening machine, a easing', a cylindrical screen memberdivided into arcuate sections, a supporting frame for each of thesections comprising parallel arcuate ribs of di'erent radius than thatof the screen member, transverse bars connecting the arcuate ribs, andprojections carried at spaced intervals by the arcuate ribs With whichthe screen member is engaged, whereby the screen will be spaced awayfrom the ribs.

24. In a pulp screening machine, a casing, a cylindrical Screen memberdivided into arcuate sections, a supporting frame for each of thesections comprising parallel arcuate ribs of dilerent radius than thatof the screen member, transverse bars connecting the arcuate ribs`r andresilient supports interposed between the screen member and the ribs.

In testimony whereof, I have hereunto set my hand this` 27th day of May,1913.

FEDER P. VESTBY.

Witnesses:

OLIVE IRWIN, y J. E. L. GOODWILL.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents, Washington, D. C.

